Power systems may include internal combustion engines that burn a hydrocarbon-based fuel to convert the potential or chemical energy stored therein to mechanical power that can be used to power other applications. The applications may be mobile such as vehicles or locomotives, stationary such as power generators, or both. The exhaust gasses that result from combusting fuel in the power system may include byproducts such as carbon oxides (CO and CO2), nitrogen oxides (NO and NO2), and particulate matter. The amount of these byproducts that may be discharged by the power system are often subject to government regulation and emissions laws. Accordingly, manufacturers of power systems have undertaken efforts to reduce or remove the regulated byproducts from the exhaust gasses. One methodology for reducing these byproducts is to employ aftertreatment systems disposed in the exhaust system downstream of the internal combustion engine that can receive the discharged exhaust gasses. For example, the aftertreatment system may include catalytic materials that convert the regulated byproducts to more benign constituents. Other systems might operate by filtering the byproducts out of the exhaust gasses.
Certain considerations may apply to the design of an aftertreatment system such as the effective exposure of the exhaust gasses to the catalytic or filtration materials. Another consideration may be the size and/or shape of the aftertreatment system so that the aftertreatment system is efficiently accommodated in the power system. One example of an aftertreatment system designed to address some of these considerations is described in U.S. Pat. No. 6,824,743 (“the '743 patent”), which describes a cylindrical housing that is closed-off at one end. The housing accommodates an annular filter element disposed around a central return pipe. Exhaust gasses may enter the housing, pass through the annular filter element toward the closed end and return through the central return pipe. The present disclosure is directed to addressing similar efficiency considerations described in the '743 patent.